Self-powered keypads printed on paper

Sheets of paper and cardboard boxes can become electronic user interfaces thanks to the work of researchers at Purdue University.

"This is the first time a self-powered paper-based electronic device is demonstrated," said Ramses Martinez, an assistant professor in Purdue's School of Industrial Engineering and in the Weldon School of Biomedical Engineering in Purdue's College of Engineering. "We developed a method to render paper repellent to water, oil, and dust by coating it with highly fluorinated molecules. This omniphobic coating allows us to print multiple layers of circuits onto paper without getting the ink to smear from one layer to the next one.

"I envision this technology to facilitate the user interaction with food packaging, to verify if the food is safe to be consumed, or enabling users to sign the package that arrives at home by dragging their finger over the box to properly identify themselves as the owner of the package," Martinez said. "Additionally, our group demonstrated that simple paper sheets from a notebook can be transformed into music player interfaces for users to choose songs, play them, and change their volume."